I don't know what the ar12 is so it is difficult to review your bag. The Nuke and the Katana aren't terribly different although depending on the wear they can be different enough to fulfill different roles.

Do you drive straight shots with the Magnet or just with the Zeppelins?

Flat shots need running on the center line of the tee and planting each step on the center line. Anhyzer needs running from rear right to front left with the plant step hitting the ground to the left of the line you're running on. Hyzer is the mirror of that.

I haven't thrown the Ace Race disc so take the other ideas with salt because the use of that disc may be overlap or perfect filling of the holes. You didn't specify how you use the Zeppelins and the Magnets. If both are for drives maybe just maybe you could do with one but i can't say for sure because i haven't put ledded to Zeps. It would be tempting to say just throw cleaner with the longer driver fh but we all know things aren't the same in the spin rate of BH vs FH and there is the matter of winds so if you can't find your dream disc in a single mold for both fh and bh you're doomed to two different discs. Less or more fade? Nuke or the Katana or something else for a single mold attempt? Possible candidates would be Katana with more fade and less flipping than Pro, more than flat topped Stars and CFR Champs -Dominator. Or a suitably weighted Blizzard Boss if more LSS ain't a problem. I'd err on the heavy side so 155+. Because winds exist. Or if you want less fade the heaviest Zero G Quasar you can get. That is way more difficult to throw fh because it flips much more than the Boss. If straight then dump fade sounds good Teedevil. It might be difficult to find that light Destroyers and now there is the matter of Vulcanized tops so Westside Sword should be better. Especially when it is thinner making fh gripping easer.

Flat shots need running on the center line of the tee and planting each step on the center line. Anhyzer needs running from rear right to front left with the plant step hitting the ground to the left of the line you're running on. Hyzer is the mirror of that.